Patent GB-970931-A (GB)
Title: Improvements relating to the manufacture of laminates
IPC: B29C63/00
Filed: 1960-10-03
Abstract: 970,931. Laminates and laminating; moulding thermoplastic sheets. OWENS-CORNING FIBERGLAS CORPORATION. Oct. 3, 1960 [Oct. 2, 1959], No. 33857/60. Headings B5A and B5N. A film of thermoplastic material such as polythene or a vinyl resin is applied to a porous body of glass or other mineral fibres by heating the film to a state of plasticity, placing it on the porous body and forcing it into intimate contact therewith by applying a pressure difference above and below the body, preferably by applying suction beneath the body with or without superposed pressure. The fibres of the porous body may be a loose aggregate or be bonded together, e.g. by phenol- or melamine-formaldehyde resin; its surface may be naturally uneven or may be figured or formed with lettering or a design, e.g. as in Fig. 5, by impressing, incizing, or adding material in the form of the design. The surfacing film may be made to adhere closely to the rugosities of the surface and may be punctured by the suction applied or, where the porous body is thin, may be absorbed into the body. A thin body may be provided with surface markings and a backing of pressuresensitive adhesive and be used as a label or adhesive panel. A similar thin body 176, 177, Fig. 11, may be adhered by the method of the invention to a thicker body 174 of mineral fibres. The porous body may be plane or shaped and the surface film may be coloured or decorated, or may include particles of pigment to assist its puncturing by the applied suction. When the film is punctured or absorbed the opposing surface of the body may be similarly covered. In further modifications (a) the film may overlap, and be adhered to, the sides of the porous body, or the film may be made to adhere, by adhesive, only to the sides of the body, which then forms an acoustic panel, (b) a heavier film may be moulded to a pattern by being applied in heated condition by suction to a porous mineral fibre body having a figured &c. surface, and being then separated from the body. Apparatus for making individual surfaced panels comprises a carriage 45, Fig. 1, having electric heating elements in its upper front 50 and movable over a hollow tray 35 holding a film 45 by means of a heavy frame 36. After heat-softening of the film the carriage is moved back and the tray 35 is lowered on guides 37 on to a porous mineral fibre tile 32 supported on a foraminous table, the area around the tile of which is masked by a sheet 33 of paper or the like. The film is drawn, by suction applied beneath the table, on to the surface and sides of the tile, and by extending the mask 33 partially beneath, and by raising the tile, may be drawn against the edge portions of its undersurface. In apparatus for continuous operation, Fig. 6, spaced panels 70 are fed on to an endless belt having foraminous portions over which the tiles are placed. A web 82 of film material is heat softened by elements 86 while passing around drums 88, 89 which are internally heated and subject to slight suction to support the film. The film is wider than the panels and is drawn down on to their upper surfaces and sides by suction applied at 79, and set by cooling rollers 90 . . . 92; the panels are then separated and surplus film cut off. Similar apparatus employing an endless belt foraminous throughout may be used to apply a heated film to a thick web of fluffy fibrous glass used for thermal and acoustic insulation.